Detergent composition



Pat rnal). 19, 1944 DETERGENT COMPOSITION "John Cecil Rhodes, Wyncote, Pa.

No Drawing.

Application January 23, 1941, Serial No. 375,619 7 v 4 Claims. ('01. 252-137) The present invention relates to a certain new and useful detergent composition and it relates more particularly to adetergent powder composition. n

An object of the present invention is to provide a detergent composition which will be emcient and economical and which will possess good wett ng and cleansing properties in hard water as well as in soft water.

Other objects and purposes of the present in- .vention are apparent in the following specification and appended claims.

For the purpose'of illustrating the invention, certain embodiments thereof are described hereinbelowit being understood however that these are given for purposes of illustration on y and that it is possible to embody the present invention in other forms without departing from the spirit thereof.

In one embodiment of the present invention I may p ovide a com osition comprising sodium metasilicate, tetrasodiurm pyrophosphate, sodium bicarbonate, a wetting agent, and sodium tetra pyrophosphate. I

As a wetting agent. I prefer .to use an organic. foaming, wetting agent or a combination of such wetting agents-as for example the composition known in the trade as Esterine or Alrosene which contains quaternary ammonium compounds of fatty acids, including those acids derived from coconut oil. I

Among the organic wetting agents which'I may use in my detergent composition are:

1) Surface active compounds prepared by react n fa ty olefines w th mono-alkyl p enolsjn the presence of sulfuric acid and subsequently neu ralizing with alkali.

2) Surface active compounds prepared by reacting fatty alcohols with mono-a kyl phenols in the presence of sulfuric acid and subsequently neutralizing with alkali.

(3) Surface active compounds prepared by condensing, in the presence of sulfuric acid. phenols with condensation products prepared from fa tv acids and alkylol amines and subsequently neutralizing with alkali.

(4) Quaternary ammonium surface active compounds with the structure where N is a nitrogen atom v 'X is a halogen R1 and R2 are aliphatic radicals containing-less than '1 carbon atoms and which may be the same or different. l

R: is an aliphatic radical containing 8 to carbon atoms which may or may not contain a sulfonic group.

R4 is an aryl or aralkyl radical which may or may I not contain one or more sulfonic groups.

X may also be any other anionic or electronegative group sum as an, hydroxyl, sulphate. or nitrate group. as exemplified, for instance, by U. S. Patent No. 2,060,850 and British Patent 443,795.

The percentage composition of the detergent constituting my present invention may be varied through quite broad limits. Thus, I have found that the sodium metasilicate may be approximately to '75 percent, the sodium carbonate from 10 to 40 percent. the sodium bicarbonate from 0 to percent, the wetting agent from 5 to 20 percent, and the tetrasodium pyrophosphate from 1 to 15 percent.

The following compositions are illustrative: (A) Detergent composition for household use:

Sodium metasilicate ten pounds (25%) Sodium carbonate 12 pounds (30%) Sodium bicarbonate 10 pounds (25%) Wetting agent (Esterine) 4 pounds (10%) Tetrasodium pyrophosphate 4 pounds (10%) (B) Detergent composition for commercial laundry use:

Sodium metasilicate 7 pounds Sodium carbonate 1 /2 pounds (15%) Sodium bicarbonate 0 pounds Wetting agent (Esterine") 1% pounds Tetrasodium pyrophosphate I have found that composition A above listed is particularly eflicient for household use especially with washing machines (both of the rotary type and of the reversing agitator type).

In preparing the detergent composition constituting one embodiment of the present invention, I may first mix the wetting agent (which is in the form of a paste as in the case of Esterine" or in the form of a liquid) with the tetrasodium pyrophosphate and the sodium carbonatethe mixing being continued until a dry powder is formed.

The sodium bicarbonate is then added with further mixing. Finally, the sodium metasilicate is added with additional mixing.

pound OFFICE" While it may be desirable in some instances to grind the finalcomposition so that a smaller particle size may be obtained, my composition may be used in-most instances without any final grinding step. I prefer to sieve the final composition.

The detergent composition making up my present invention, is used simply by adding a small amountlas for example 1%) to the water which is to be used in the washing operation. The addition of my detergent composition results in the formation of .a quick, copious and stable foam or suds. The composition is highly effective in removing dirt, grease and other stains and spots from clothing, and otherlaundered articles and for all other wet cleaning purposes.

The composition of the present invention has, at the same time, a gentle cleansing action and maybe used safely upon the great majority of laundered articles. As hereinabove stated, the

' composition of the present invention will produce abundant and immediate suds or foam even in hard water and will prevent the formation of the characteristic gray scum or deposit which results when ordinary soaps or soap powders are added to hard water.

In 1% solution, my present composition will give a pH of approximately 9.0 to 11.5.

While I do not wish to be bound thereby, I believe that the function of the several ingredients and the action of the final composition may be explained as follows:

The sodium carbonate and sodium bicarbonate give a buffer action and act to reduce the relatively strong alkalinity of the sodium metasilicate. In one percent solution, the sodium metasilicate has a pH of approximately 12.3 the sodium carbonate 11.4. and the sodium bicarbonate 8. When the three above-listed ingredients: are mixed, the mixture in l solution has a pH of approximately so that the mixture is less strongly alkaline than the sodium metasilicate itself.

The sodium carbonate also prevents the caking which results when sodium metasilicate and sodium bicarbonate are mixed alone-the sodium carbonate acting as a diluent to prevent the interaction of the other two constituents and to absorb any water which would cause reaction and caking and the formation of less soluble silicates.

The wetting agent performs the usual functions of such a material in a detergent composition giving an emulsifying, wetting, and desorbing action. I- prefer to use the synthetic organic wetting agents above described since these are more effective than the ordinary soaps or soap powders.

The tetrasodium pyrophosphate has several functions in my present composition; During the preparation of the composition, it acts\to dry the mixture by combining with the water present-' the adsorbed and absorbed water being converted to water of crystallization.

The tetrasodium pyrophosphate also acts to increase the foaming efiect of the wetting agent.

The primary efiect of the tetrasodium pyrophosphate is the softening of the water to be used during the laundering period. I believe that this is accomplished by the formation of a calciumpyrophosphate complexion which is soluble, very stable and very slightly dissociated so that the calcium, which is normally present in hard water is immobilized and tied up to such an extent that the formation of insoluble calcium salts (which constitute the scum usually formed when hard water is used in washing) is prevented.

pyrophosphate in substantially unreacted form,

to water taken up from the ample the orthosilicate may be used-in which case the buffer mixture ratio should be changed to correspond with the change in the degree of alkalinity of the silicate.

In place of the tetrasodium pyrophosphate it is possible to use the partially neutralized pyrophosphates as for example the di-sodium pyrophosphate NazHzPzO'r.

It is also possible to use other phosphates such as the orthophosphate and the hexametaphosphate.

When silicates less alkaline than the metasilicate are used, it is possible to eliminate pant or all of the bicarbonate.

For specific purposes, where a detergent composition giving a high pH is desired, the metasilicate may be used with part orall of the bicarbonate eliminated.

Borax may be used to replace part of the carbonate and bicarbonate since it gives similar buffer and diluent action.

Metaborate may be used to replace part of the metasilicate although generally somewhat more expensive.

Other alkali metal salts may be used in place of the sodium salts described hereinabove.

The present invention may be embodied in other forms and it is therefore desired that the scope of the present invention be determined by the following claims rather than the foregoing specification.

Having thus 'described the invention, what is hereby claimed as new and desired to be secured by Letters Patent is:

1. A finely divided free-flowing non-caking readily water-soluble detergent powder composition comprising by weight about25 to sodium metasilicate, 10 to 40% sodium carbonate, an effective amount up to 35% sodium bicarbonate, 5 to 20% of an organic wetting agent and 1 to 15% tetrasodium pyrophosphate in substantially unreacted form, said composition having a pH about 9 to about 11.5 in about 1% by weight aqueous solution. 7

2. A finely divided free-flowing non-caking readily water-soluble detergent powder composition comprising by weight about 25 to 75% of an alkali metal metasilicate, 10 to 40% of an alkali metal carbonate, an effective amount up to 35% alkali metal bicarbonate, 5 to 20% of an organic wetting agent and 1 to 15% of an alkali metal said composition having a. pH about 9 to about 11.5 in about 1% by weight aqueous solution.

3. A finely divided free-flowing non-caking readily water-soluble detergent powder composition comprising by weight about 25% sodium metasilicate, 30% sodium carbonate, 25% sodium bicarbonate, 10% of an organic wetting agent, and 10% tetrasodium pyrophosphate.

4. An aqueous detergent bath comprising an aqueous solution of the composition defined in claim 1.

J. CECIL RHODES.

of time without caking or. 

